Gene/Protein Disease Symptom Drug Enzyme Compound
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Query: UMLS:C0029463 (osteosarcoma)
 16,637 document(s) hit in 31,850,051 MEDLINE articles (0.00 seconds)

In order to characterize fibroblastic colony-forming units (CFU-F) from murine bone marrow in relation to osteogenesis, adherent cells of 7-day-old BALB/c mouse bone marrow cultures were infected with a recombinant retrovirus (N2/ delta fosB) containing the bacterial neomycin resistance gene. One of the G418-resistant clones, MN7, was selected for further analysis on the basis of its high expression of the bone-specific alkaline phosphatase. The cells have now been in culture for more than 1 year and maintain a stable phenotype. The osteogenic nature of the immortalized clone MN7 was demonstrated as follows: (1) Mineralization was detected by 85Sr uptake and with the Von Kossa staining method only after in vitro cultivation on a collagen type I matrix. (2) Osteoblastic phenotype markers, including the synthesis of type I collagen, osteonectin, and the bone-specific isoenzyme of alkaline phosphatase were expressed in vitro. (3) MN7 cells responded to bone effectors such as parathyroid hormone and 1,25-dihydroxyvitamin D3. (4) Intraperitoneal injection of MN7 cells into 1-day-old BALB/c mice produced typical osteosarcomas in all animals. We conclude that MN7, derived entirely in vitro from a stromal CFU-F colony, represents a stable murine osteosarcoma cell line expressing the osteoblastic phenotype and provides the first direct evidence needed to establish adult mouse marrow-derived, nonhematopoietic stromal cells as osteoprogenitors.
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PMID:Establishment of an osteogenic cell line derived from adult mouse bone marrow stroma by use of a recombinant retrovirus. 157 49

The murine retrovirus shuttle vector pZipNeo SV(X)1 was used to construct plasmids encoding the three major surface glycoproteins of bovine herpesvirus-1 (BHV-1). Each plasmid was transfected into D17, a canine osteosarcoma cell line sensitive to lysis by bovine NK-like cells when infected with BHV-1. After selection in G418 sulfate, cell lines expressing the recombinant gene products were sorted by flow microfluorimetry, radioimmunoprecipitated, and analyzed by SDS-PAGE for fidelity as compared to the native viral glycoproteins. Two of the three genetically engineered cell lines (gI and gIV) could successfully serve as targets to detect bovine NK-like cytolysis. These findings support and extend a previous study from our laboratory indicating a role for BHV-1 glycoproteins in the cytolytic response by bovine NK-like cells. Additionally, this study demonstrated that individual proteins are recognized by these effector cells, and that recombinant glycoproteins can direct cytolytic activity in the absence of host cell infection-associated proteins. This is the first known report of Ag directed cytotoxicity by bovine null (non-B, non-T) cells.
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PMID:Bovine natural killer-like cell responses against cell lines expressing recombinant bovine herpesvirus type 1 glycoproteins. 216 95

Internal irradiation of mice using bone seeking radionuclides results in the activation of endogenous retroviruses and in the subsequent development of bone tumors. Genomic DNA from an osteosarcoma cell line, derived from an 90Sr-induced bone tumor, was cotransfected with the plasmid pSV2-neo into NIH/3T3 cells and G418-resistant transfectants gave rise to colonies in soft agar. Southern blot analysis of these first cycle transformants revealed the presence of extra copies of c-ras. We have analysed the arrangement of ecotropic murine leukemia proviral sequences in seven 90Sr-induced bone tumors and one osteosarcoma cell line of CF1-mice. Integration of ecotropic and/or ecotropic recombinant proviruses seems to be involved in rearrangements of 3' provirus cellular junction fragments occurring in all tumor DNAs analysed, but no indication for site-specific integration was found. We also determined the primary structure of FBR-MuSV, a transforming retrovirus able to induce bone tumors in newborn mice. FBR-MuSV contains sequences from all four exons of the murine c-fos gene, but lacks sequences encoding the first 24 and the last 98 amino acids of the c-fos gene product. The coding region of FBR-MuSV has also undergone two small in frame deletions. Thus, the v-fosFBR-MuSV retains 236 amino acids of the 380 amino acids of the murine c-fos product. In FBR-MuSV-transformed cells two fos-containing mRNAs have been detected: a 3.3-kb full-size genomic RNA and a 2.2-kb subgenomic mRNA as revealed by both fos- and MuLV-hybridization probes.
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PMID:Oncogene involvement in radiation- and virus-induced mouse osteosarcomas. 301 18

The human osteosarcoma cell line, MG63, responds both to GM-CSF and to G-CSF in vitro. To assess the significance of these observations to tumor growth in vivo, MG63 cells were engineered by retroviral infection to produce human GM-CSF or G-CSF. These retrovirally infected cells become autostimulatory as measured by increased [3H]-thymidine incorporation (3- to 7-fold) and anchorage-independent colony formation (7- to 10-fold) as compared with uninfected MG63 cells or cells infected with control (neor) retrovirus. The increased proliferation induced by exogenous GM-CSF or G-CSF on uninfected MG63 cells in both assays could be completely inhibited by anti-GM-CSF or anti-G-CSF antibodies, while the same antibodies only partially abrogated proliferation by the growth-factor-producing cells. None of 34 nude or SCID mice developed tumors when injected s.c. with uninfected or neor-virus-infected cells. In contrast, all 30 mice injected with GM-CSF- or G-CSF-producing MG63 cells developed tumors which were G418-resistant and factor-producing. Tumor cell DNA showed a polyclonal retroviral integration pattern indistinguishable from that in the DNA of cells injected into mice. Tumors that formed following injection of a mixture of G418-resistant, GM-CSF-producing cells and cells infected with virus containing only the hygror gene contained hygromycin-resistant cells in the same proportion as was present in the original cell mixture. These data indicate that GM-CSF and G-CSF can support the growth of an osteosarcoma cell line both in vitro and in vivo whether the factor is supplied by autocrine production or from exogenous sources.
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PMID:The effect of GM-CSF and G-CSF on the growth of human osteosarcoma cells in vitro and in vivo. 750 89

Bone morphogenetic proteins (BMP) play a pivotal role in growth and differentiation of osteoblastic lineage cells. BMPs are potent stimulators of bone formation in various animal models. To understand the mechanism of BMP action in bone cells, we have investigated the effects of overexpression of the BMP-2 gene on proliferation and differentiation of UMR-106 rat osteosarcoma cells. A stable UMR-106 cell line overexpressing the BMP-2 gene was established by transfection of cells using a mammalian expression vector harboring human BMP-2 cDNA followed by G418 selection. After introduction of the BMP-2 gene, UMR-106 cells appeared more spindle-shaped in morphology compared to the predominantly cuboidal appearance of the parental cells. Overexpression of BMP-2 markedly inhibited proliferation as measured by cell counting and [3H]thymidine incorporation assays. Extracellular matrix (ECM) derived from cells overexpressing BMP-2 exhibited a less supportive effect on proliferation of UMR cells than did ECM derived from parental cells. Furthermore, cell-cell communication through gap junctions was reduced more than 50% as determined by nondisruptive fluorescent dye transfer assays. Overexpression of BMP-2 significantly stimulated expression of osteocalcin and alkaline phosphatase genes, indicating its role in osteoblastic differentiation. There was little effect on osteopontin gene expression.
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PMID:Overexpression of BMP-2 modulates morphology, growth, and gene expression in osteoblastic cells. 1190 Apr 83

We have constructed a single plasmid-, Tc1-like transposon-based gene transfer vector, termed the Prince Charming vector (pPC). The pPC vector was constructed by ligating the CMV-driven "Sleeping Beauty" transposase gene downstream to the Tc1-like transposon inverted repeat (IR) elements and by inserting the RSV promoter (to drive expression of the gene-of-interest) along with a multiple cloning site (MCS), a polyadenylation signal, and the SV40 promoter-driven neomycin gene, at a site flanked by the transposon IR elements. To assess the utility of the pPC vector, we cloned a red fluorescent protein (RFP) gene into the pPC vector at the MCS and transfected human TE85 osteosarcoma cells with the pPC-RFP expression vector using Effectene. Stable transgenic cell clones expressing RFP were selected with G418 sulfate and individual clones were isolated. After 4 weeks of clonal isolation and expansion, 99% of cells in each randomly selected clone expressed RFP strongly. Aliquots of each clone were then maintained in either the presence or the absence of G418 sulfate and were passaged weekly. Even after 6 months in culture in the absence of G418 sulfate, approximately 90% of the cells in each clone still maintained a strong expression level of RFP, indicating that these transgenic cell clones were stable and that the clonal stability of these clones did not require a constant selection pressure. In conclusion, we have developed a single plasmid-, Tc1-like transposon-based gene transfer vector that can be used to generate stable transgenic mammalian cell clones.
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PMID:Construction of a Tc1-like transposon Sleeping Beauty-based gene transfer plasmid vector for generation of stable transgenic mammalian cell clones. 1241 68

To study the effect on regulation of cell cycle of osteosarcoma cell line MG63 tranceduced with exogenous p16ink4a and hRb1 genes, pIRES-p16ink4a-hRb1, pIRES-p16ink4a and pIRES-hRb1 plasmids were constructed by gene recombination technology. The recombinant plasmid was transferred into osteosarcoma cell line MG63 by metafectene, and the resistant clones were selected by G418 selective medium. mRNA and protein expression of osteosarcoma cell line were assayed by RT-PCR and Western-Blot respectively. Cell cycle and apoptosis were analyzed by subG1 flow cytometric. Cell proliferation was tested by MTT. In the genome of these transfected target cells, the expression of p16ink4a and hRb1 mRNA and protein were detected respectively in vitro. It was demonstrated with subG1 flow cytometric analysis and MTT method that p16ink4a and hRb1 genes cooperation more significantly inhibited cell growth and induced a more marked G1 arrest and apoptosis than p16ink4a/hRb1 alone (P < 0.01). Coexpression of exogenous p16ink4a with hRb1 broke the regulatory feedback loop of p16ink4a-cyclinD1 /CDK-hRb1 and played a more significant role in inhibiting cell growth as well as inducing cell apoptosis than p16ink4a or hRb1 did alone in vitro.
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PMID:Effect of exogenous p16ink4a and hRb1 genes on cell cycle regulation of osteosarcoma cell. 1669 24